Biomedical subjects

D Walther

Publications and source records attributed to D Walther.

At least 55 records · Page 3Linked to original sources

PubMed1993

Ligature-induced peri-implant infection in cynomolgus monkeys. I. Clinical and radiographic findings.

The purpose of this study was to compare the effect of plaque accumulation in conjunction with or without placement of plaque-retaining ligatures on peri-implant and periodontal tissues. Four cynomolgus monkeys received 2 ITI (Type F) dental implants in edentulous areas of each side of the mandible. Following a healing period of 2 months with regular prophylaxis procedures twice per week, plaque was allowed to accumulate. After 1 month (day 0), silk ligatures were placed around 1 of the 2 implants. The third molars served as controls and were ligated as well. Clinical examinations comprising Plaque Index (PlI), Gingival Index (GI), probing depth (PD) and loss of attachment (LA) were performed at the test and control sites before and 1, 2, 3, 4, 5, 6, 7 and 8 months after ligature placement. Sixty and 30 days prior to ligation and at 2, 5, 6 and 8 months following ligation, standardized radiographs were obtained and subtracted from a baseline radiograph obtained at the time of ligation. PlI and GI scores increased significantly following the elimination of prophylaxis procedures. After ligation, these indices continued to increase and reached values significantly higher in ligated implant (LI) and ligated teeth (LT) sites than in non-ligated teeth (NLI) sites. PD also increased after plawue accumulation and ligature placement. Significantly greater PD values were noted in LI and LT sites than in NLI sites.(ABSTRACT TRUNCATED AT 250 WORDS)

Alveolar Bone Loss↗

PubMed1992

Dopamine transporter mRNA: dense expression in ventral midbrain neurons.

Oligonucleotides and a full-length cDNA encoding a functional dopamine transporter (DAT1) hybridize to a 3.7 kb mRNA that is concentrated in mRNA prepared from midbrain and absent in specimens from cerebellum or cerebral cortex. In situ hybridization reveals substantial hybridization densities overlying neurons of the substantia nigra, pars compacta, and the parabrachialis pigmentosus region of the ventral tegmental area (VTA). Neurons in the linear and paranigral VTA regions display lower levels of expression. Preliminary studies in arcuate neurons suggest modest hybridization. Different dopaminergic cell groups display different levels of DAT1 dopamine transporter expression.

Animals↗

PubMed1992

[Microbiological studies of self-disinfecting alginate impression materials].

Using microbiologically experimental methods and observations corresponding to praxis the efficiency of the addition of antiseptics to alginate is evaluated. The addition of chlorhexidine to the alginate leads to a considerable reduction of the amounts of germs, but an one hundred percent disinfection of the alginates is not always performed. An influence of the alginate materials and the water quality on the antimicrobial efficacy of chlorhexidine has been proved. The always occurring contamination of the impression tray rules out a complete stopping of infection between the patient and the laboratory staff.

Alginates↗

PubMed1991

Jun B, c-jun, jun D and c-fos mRNAs in nucleus caudalis neurons: rapid selective enhancement by afferent stimulation.

In situ hybridization using cDNAs complementary to specific regions of the mRNAs encoding 3 members of the jun transcription factor gene family and c-fos reveals modest levels of hybridization over superficial laminae of the nucleus caudalis of the spinal tract of the trigeminal in sections taken from unstimulated brains. Jun B expression is markedly and rapidly enhanced ipsilateral to electrical stimulation of the trigeminal ganglion. C-fos mRNA levels also show changes, especially after higher intensity stimulation. Smaller alterations in c-jun (jun A) and jun D do not reach statistical significance. In each instance of altered expression, more neurons express hybridization densities above background levels after stimulation. Parallels between these alterations and changes in the expression of preproenkephalin in these same neuronal populations are discussed.

Afferent Pathways↗

PubMed1989

[Sonographic findings in silicone-induced granulomas and lymphadenopathy following mammaplastic surgery].

Ultrasound examination of the breast and its lymphatic drainage was undertaken in 78 patients who--after mammoplasty with silicone implants--had palpable lymph nodes, pain and sensation of tension in the area surrounding the implant. Five patients had space-occupying echo-dense inner structures and dense echos from structures dorsal to the space-occupying ones. In this way silicone granuloma could be demonstrated even preoperatively in tissues, musculature or lymph nodes, although the changes were palpable in only two of the five patients. Ultrasonography can thus be of great importance not only in the diagnosis but also in the preoperative localization of silicone-induced granulomas.

Adult↗

PubMed1989

[In vitro microbiological research on oral ointments].

Two oral ointments were investigated of their antimicrobial activities using agar diffusion test and suspension method with aerobic germs and Candida albicans. The oral ointment Parodontal-Mundsalbe-neu was better then Parodontal-Mundsalbe-alt with regard to intensity, begin and end of action. In our experiments the field of activity of both ointments against the species tested was identically.

Administration, Topical↗

PubMed1987

Ceftriaxone given repeatedly cures manifest syphilis in the rabbit.

Repeated intramuscular injection of ceftriaxone to rabbits with manifest syphilitic orchitis leads to clinical cure as does penicillin, given the serum levels reached are similar to the ones obtained clinically in man. Totally different to untreated controls the Treponema pallidum hemagglutination (TPHA) titers remain relatively low and later even tend to decrease further. Thus, it seems justified to start clinical trials on the definite role of ceftriaxone in the treatment of clinical syphilis.

Animals↗

PubMed1986

Comparative in vitro susceptibility of Treponema pallidum to ceftizoxime, ceftriaxone and penicillin G.

A procedure dating back to the early penicillin era is adapted in order to determine the activity of the new cephalosporins ceftizoxime and ceftriaxone against Treponema pallidum in vitro. While the well-known activity of penicillin G is confirmed for the virulent Nichols strain (0.002 micrograms/ml lead to 50% immobilisation) the new cephalosporins turn out to be almost as efficacious. The concentration of ceftizoxime leading to 50% inhibition amounts to 0.004 micrograms/ml. The corresponding figure for ceftriaxone is 0.01 micrograms/ml. The potential importance of these findings for the treatment of syphilis in man are discussed.

Animals↗

PubMed1980

[Radioimmunologic technics for luteinizing hormone determination in cattle and sheep].

The antigen relationship which exists between luteinising hormone of various animal species, on the one hand, and human luteinising hormone as well as human chorionic gonadotrophin, on the other, was the background against which possible approaches were tested to the preparation of a heterologous in-vitro test for serum LH determination in cattle and sheep. The following conclusions may be drawn from the results so far obtained: --A homologous or heterologous test with specific relevance to the determination of human LH, on the basis of hLH-anti-hLH or hLH-anti-hCG is not suitable for the determination of LH in animal serum (cattle, sheep). --Quantitative and specific measurement of LH concentrations in the blood of cattle (sheep) is possible by means of an ovine-LH-anti-ovine/bovine-LH (or anti-bovine-LH) test system which is based on cross-reactivity between luteinising hormones of cattle and sheep. --Differentiated measurement of various LH concentrations in animal serum will be possible under certain specific assay conditions, with ovine LH as tracer, ovine or bovine LH as standard, and hCG antiserum. Yet, the clinical value of that heterologous radio-immuno-assay method is attributable primarily to its potential to measure peak values within the cycle to determine the time of ovulation rather than to the built-in possibility to determine base values of the cycle.

Animals↗

PubMed1979

Interstitial cell tumor of testis: a delicate problem.

Interstitial cell tumor of the testis is a rare tumor in humans. There have been 39 cases reported in children and 13 malignant tumors in adults. Two cases of interstitial cell tumor in childhood, 5 benign types in adults, and 2 malignant tumors are presented herein. In regard to the therapeutic consequences, a plea is made to define the malignant potential of the tumor on histologic criteria alone.

Adult↗

PubMed1973